This was the post I gave to someone else yesterday with the same complaint, though I have to say I think the machine itself is beautiful to use, and I love it.
Your problem may be the weight [too light] of the encoders on the tracks, they do not press down hard enough, this in turn affects the stitch regulater. I bought a TL 18 few years ago and had the same happen to me. Sometimes the needle would stay down in the fabric for 5/6 stitches, and it took me nearly 3 yrs to find the cause and fix, both encoders were involved. I bought some mechano-like bits from the hardware store and attached to the back of the carriage, then wedged some styro chunks between that and the tops of the encoders. It has fixed my problem. Even the shop I bought it from wouldn't admit to knowledge of this. I was sent new encoders, but the same again. The dealer must have known about it, because now , at the shows, they have a new carriage with different encoders. You should be very persistant in making your dealer fix this or return your money. [easy for me to say] But these things cost too much money to have so much trouble.
Will try posting a photo of my encoders, yours may not be the same.
Hope this helps you, it nearly drove me nuts.
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